Ultrasound elastography: A novel user-independent quasi-static method

Abstract

Quasi-static ultrasound elastography is a popular clinical ultrasound modality which can give measures of the relative stiffness of a region of interest [1]. Tumours have been well documented to have different mechanical properties than the surrounding healthy tissue [2]. Ultrasound elastography techniques take advantage of this contrast to create stiffness maps of soft tissue called elastograms, with these, the tumours can be easily distinguished from the healthy tissue [1]. Current quasi-static methods require the user to manually palpate the region of interest with the ultrasound probe, which can lead to user-user variability when imaging [3]. We propose a novel, user-independent method where external palpation is provided by means of a stepper motor via the perineum. A tissue-mimicking agar phantom of the prostate was created and imaged using a transrectal probe. An elastography algorithm was then developed using MATLAB and inclusions of varying stiffness and sizes were successfully delineated from the surrounding soft tissue.